In a useful method for the fabrication of color filter elements for solid state electronic color image sensing devices, for example, CCD, CID and MOS devices, dyed filter elements are formed by coating photopatternable layers, imagewise exposing, washing off unexposed layer portions and then dyeing the remaining filter layer by dye imbibition. In one approach, a hydrophilic colloid, for example, gelatin, can be suspended in water along with a radiation responsive hardening (i.e., crosslinking) agent to form the photopatternable composition. In another approach, a diazo resin can be mixed with a mordant to produce a photopatternable composition to form the dyeable filter elements. These approaches are described, for example, in U.S. Pat. No. 4,764,670.
However, these and other approaches have not been entirely satisfactory. For example, the step of dyeing the exposed filter layer by dye imbibition generally leads to swelling of the image layer. Also, these approaches generally require the use of interlayers (so-called barrier layers) to prevent the dyes from migrating between contiguous filter layers. Dye wandering or leaching leads to undesirable non-uniform dye densities and decreases in image resolution. It would be desirable to provide a pre-dyed resist composition which does not suffer from image swelling as in the case of post-dyed resist systems. Perhaps more importantly, it would be highly desirable to provide a resist composition for a color filter array system which does not require the use of barrier layers.